The per-processor interrupt request register and current processor
priority register are only accessed on the current cpu. In fact the
hypervisor doesn't even let us choose which cpu's registers to access.
The only function to use cpu twice is xics_migrate_irqs_away, not a fast
path. But we can cache the result of get_hard_processor_id() instead of
calling get_hard_smp_processor_id(cpu) in a loop across the call to rtas.
Years ago the irq code passed smp_processor_id into get_irq, I thought
we might initialize the CPPR third party at boot as an extra measure of
saftey, and it made the code symmetric with the qirr (queued interrupt
for software generated interrupts), but now it is just extra and
sometimes unneeded work to pass it down.
Signed-off-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
On a POWER6 machine running 2.6.23-rc8 I sometimes see the following error:
xics_set_affinity: No online cpus in the mask 00000000,00000000,00000000,00000001 for irq 20
In a desperate attempt to get a changelog entry in 2.6.23, I took a look
into it.
It turns out we are passing a real and not a virtual irq into
get_irq_server. This works for the case where hwirq < NR_IRQS and we
set virq = hwirq. In my case however hwirq = 590082 and we try and
access irq_desc[590082], slightly past the end at 512 entries.
Lucky we ship lots of memory with our machines.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
The majority of irq_host implementations (3 out of 4) are associated
with a device_node, and need to stash it somewhere. Rather than having
it somewhere different for each host, add an optional device_node pointer
to the irq_host structure.
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In some of the PPC970 based systems, interrupt would be distributed to
offline cpus also even when booted with "maxcpus=1". So check whether
cpu online map and cpu present map are equal or not. If they are equal
default_distrib_server is used as interrupt server otherwise boot cpu
(default_server) used as interrupt server.
In addition to this, if an interrupt is assigned to a specific cpu (ie
smp affinity) and if that cpu is not online, the earlier code used to
return the default_distrib_server as interrupt server. This
introduces an additional parameter to the get_irq function, called
strict_check. Based on this parameter, if the cpu is not online
either default_distrib_server or -1 is returned.
Signed-off-by: Mohan Kumar M <mohan@in.ibm.com>
Cc: Michael Ellerman <michael@ellerman.id.au>
Acked-by: Milton Miller <miltonm@bga.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In 616883df78 request_irq was marked as
__must_check so we must... er... check it.
Signed-off-by: Michael Neuling <mikey@neuling.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
for consistency with other Open Firmware interfaces (and Sparc).
This is just a straight replacement.
This leaves the compatibility define in place.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Acked-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This is more consistent and gets us closer to the Sparc code.
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We can use default_server when masking an interrupt vector.
get_irq_server() assumes a virtual irq, so badness may happen if we
give it a real one.
Signed-off-by: Michal Ostrowski <mostrows@watson.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This allows any secondary CPU thread also to become boot cpu for
POWER5. The patch is required to solve kdump boot issue when the
kdump kernel is booted with parameter "maxcpus=1". XICS init code
tries to match the current boot cpu id with "reg" property in each CPU
node in the device tree. But CPU node is created only for primary
thread CPU ids and "reg" property only reflects primary CPU ids. So
when a kernel is booted on a secondary cpu thread above condition will
never meet and the default distribution server is left as zero. This
leads to route the interrupts to CPU 0, but which is not online at
this time.
We use ibm,ppc-interrupt-server#s to check for both primary and
secondary CPU ids. Accordingly default distribution server value is
initialized from "ibm,ppc-interrupt-gserver#s" property. We loop
through ibm,ppc-interrupt-gserver#s property to find the global
distribution server from the last entry that matches with boot cpuid.
Signed-off-by: Mohan Kumar M <mohan@in.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Remove struct pt_regs * from all handlers.
Also remove the regs argument from get_irq() functions.
Compile tested with arch/powerpc/config/* and
arch/ppc/configs/prep_defconfig
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.
The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around. On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).
Where appropriate, an arch may override the generic storage facility and do
something different with the variable. On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.
Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions. Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller. A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.
I've build this code with allyesconfig for x86_64 and i386. I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.
This will affect all archs. Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:
struct pt_regs *old_regs = set_irq_regs(regs);
And put the old one back at the end:
set_irq_regs(old_regs);
Don't pass regs through to generic_handle_irq() or __do_IRQ().
In timer_interrupt(), this sort of change will be necessary:
- update_process_times(user_mode(regs));
- profile_tick(CPU_PROFILING, regs);
+ update_process_times(user_mode(get_irq_regs()));
+ profile_tick(CPU_PROFILING);
I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().
Some notes on the interrupt handling in the drivers:
(*) input_dev() is now gone entirely. The regs pointer is no longer stored in
the input_dev struct.
(*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking. It does
something different depending on whether it's been supplied with a regs
pointer or not.
(*) Various IRQ handler function pointers have been moved to type
irq_handler_t.
Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
Noticing the following might_sleep warning (dump_stack()) during kdump
testing when CONFIG_DEBUG_SPINLOCK_SLEEP is enabled. All secondary CPUs
will be calling rtas_set_indicator with interrupts disabled to remove
them from global interrupt queue.
BUG: sleeping function called from invalid context at
arch/powerpc/kernel/rtas.c:463
in_atomic():1, irqs_disabled():1
Call Trace:
[C00000000FFFB970] [C000000000010234] .show_stack+0x68/0x1b0 (unreliable)
[C00000000FFFBA10] [C000000000059354] .__might_sleep+0xd8/0xf4
[C00000000FFFBA90] [C00000000001D1BC] .rtas_busy_delay+0x20/0x5c
[C00000000FFFBB20] [C00000000001D8A8] .rtas_set_indicator+0x6c/0xcc
[C00000000FFFBBC0] [C000000000048BF4] .xics_teardown_cpu+0x118/0x134
[C00000000FFFBC40] [C00000000004539C]
.pseries_kexec_cpu_down_xics+0x74/0x8c
[C00000000FFFBCC0] [C00000000002DF08] .crash_ipi_callback+0x15c/0x188
[C00000000FFFBD50] [C0000000000296EC] .smp_message_recv+0x84/0xdc
[C00000000FFFBDC0] [C000000000048E08] .xics_ipi_dispatch+0xf0/0x130
[C00000000FFFBE50] [C00000000009EF10] .handle_IRQ_event+0x7c/0xf8
[C00000000FFFBF00] [C0000000000A0A14] .handle_percpu_irq+0x90/0x10c
[C00000000FFFBF90] [C00000000002659C] .call_handle_irq+0x1c/0x2c
[C00000000058B9C0] [C00000000000CA10] .do_IRQ+0xf4/0x1a4
[C00000000058BA50] [C0000000000044EC] hardware_interrupt_entry+0xc/0x10
--- Exception: 501 at .plpar_hcall_norets+0x14/0x1c
LR = .pseries_dedicated_idle_sleep+0x190/0x1d4
[C00000000058BD40] [C00000000058BDE0] 0xc00000000058bde0 (unreliable)
[C00000000058BDF0] [C00000000001270C] .cpu_idle+0x10c/0x1e0
[C00000000058BE70] [C000000000009274] .rest_init+0x44/0x5c
To fix this issue, rtas_set_indicator_fast() is added so that will not
wait for RTAS 'busy' delay and this new function is used for kdump (in
xics_teardown_cpu()) and for CPU hotplug ( xics_migrate_irqs_away() and
xics_setup_cpu()).
Note that the platform architecture spec says that set-indicator
on the indicator we're using here is not permitted to return the
busy or extended busy status codes.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Our pseries hcall interfaces are out of control:
plpar_hcall_norets
plpar_hcall
plpar_hcall_8arg_2ret
plpar_hcall_4out
plpar_hcall_7arg_7ret
plpar_hcall_9arg_9ret
Create 3 interfaces to cover all cases:
plpar_hcall_norets: 7 arguments no returns
plpar_hcall: 6 arguments 4 returns
plpar_hcall9: 9 arguments 9 returns
There are only 2 cases in the kernel that need plpar_hcall9, hopefully
we can keep it that way.
Pass in a buffer to stash return parameters so we avoid the &dummy1,
&dummy2 madness.
Signed-off-by: Anton Blanchard <anton@samba.org>
--
Signed-off-by: Paul Mackerras <paulus@samba.org>
Now that get_property() returns a void *, there's no need to cast its
return value. Also, treat the return value as const, so we can
constify get_property later.
pseries platform changes.
Built for pseries_defconfig
Signed-off-by: Jeremy Kerr <jk@ozlabs.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch slightly reworks the new irq code to fix a small design error. I
removed the passing of the trigger to the map() calls entirely, it was not a
good idea to have one call do two different things. It also fixes a couple of
corner cases.
Mapping a linux virtual irq to a physical irq now does only that. Setting the
trigger is a different action which has a different call.
The main changes are:
- I no longer call host->ops->map() for an already mapped irq, I just return
the virtual number that was already mapped. It was called before to give an
opportunity to change the trigger, but that was causing issues as that could
happen while the interrupt was in use by a device, and because of the
trigger change, map would potentially muck around with things in a racy way.
That was causing much burden on a given's controller implementation of
map() to get it right. This is much simpler now. map() is only called on
the initial mapping of an irq, meaning that you know that this irq is _not_
being used. You can initialize the hardware if you want (though you don't
have to).
- Controllers that can handle different type of triggers (level/edge/etc...)
now implement the standard irq_chip->set_type() call as defined by the
generic code. That means that you can use the standard set_irq_type() to
configure an irq line manually if you wish or (though I don't like that
interface), pass explicit trigger flags to request_irq() as defined by the
generic kernel interfaces. Also, using those interfaces guarantees that
your controller set_type callback is called with the descriptor lock held,
thus providing locking against activity on the same interrupt (including
mask/unmask/etc...) automatically. A result is that, for example, MPIC's
own map() implementation calls irq_set_type(NONE) to configure the hardware
to the default triggers.
- To allow the above, the irq_map array entry for the new mapped interrupt
is now set before map() callback is called for the controller.
- The irq_create_of_mapping() (also used by irq_of_parse_and_map()) function
for mapping interrupts from the device-tree now also call the separate
set_irq_type(), and only does so if there is a change in the trigger type.
- While I was at it, I changed pci_read_irq_line() (which is the helper I
would expect most archs to use in their pcibios_fixup() to get the PCI
interrupt routing from the device tree) to also handle a fallback when the
DT mapping fails consisting of reading the PCI_INTERRUPT_PIN to know wether
the device has an interrupt at all, and the the PCI_INTERRUPT_LINE to get an
interrupt number from the device. That number is then mapped using the
default controller, and the trigger is set to level low. That default
behaviour works for several platforms that don't have a proper interrupt
tree like Pegasos. If it doesn't work for your platform, then either
provide a proper interrupt tree from the firmware so that fallback isn't
needed, or don't call pci_read_irq_line()
- Add back a bit that got dropped by my main rework patch for properly
clearing pending IPIs on pSeries when using a kexec
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Paul Mackerras <paulus@samba.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This adds the new irq remapper core and removes the old one. Because
there are some fundamental conflicts with the old code, like the value
of NO_IRQ which I'm now setting to 0 (as per discussions with Linus),
etc..., this commit also changes the relevant platform and driver code
over to use the new remapper (so as not to cause difficulties later
in bisecting).
This patch removes the old pre-parsing of the open firmware interrupt
tree along with all the bogus assumptions it made to try to renumber
interrupts according to the platform. This is all to be handled by the
new code now.
For the pSeries XICS interrupt controller, a single remapper host is
created for the whole machine regardless of how many interrupt
presentation and source controllers are found, and it's set to match
any device node that isn't a 8259. That works fine on pSeries and
avoids having to deal with some of the complexities of split source
controllers vs. presentation controllers in the pSeries device trees.
The powerpc i8259 PIC driver now always requests the legacy interrupt
range. It also has the feature of being able to match any device node
(including NULL) if passed no device node as an input. That will help
porting over platforms with broken device-trees like Pegasos who don't
have a proper interrupt tree.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
This adapts the generic powerpc interrupt handling code, and all of
the platforms except for the embedded 6xx machines, to use the new
genirq framework.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Use the new IRQF_ constants and remove the SA_INTERRUPT define
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
Consolidation: remove the irq_affinity[NR_IRQS] array and move it into the
irq_desc[NR_IRQS].affinity field.
[akpm@osdl.org: sparc64 build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This patch-queue improves the generic IRQ layer to be truly generic, by adding
various abstractions and features to it, without impacting existing
functionality.
While the queue can be best described as "fix and improve everything in the
generic IRQ layer that we could think of", and thus it consists of many
smaller features and lots of cleanups, the one feature that stands out most is
the new 'irq chip' abstraction.
The irq-chip abstraction is about describing and coding and IRQ controller
driver by mapping its raw hardware capabilities [and quirks, if needed] in a
straightforward way, without having to think about "IRQ flow"
(level/edge/etc.) type of details.
This stands in contrast with the current 'irq-type' model of genirq
architectures, which 'mixes' raw hardware capabilities with 'flow' details.
The patchset supports both types of irq controller designs at once, and
converts i386 and x86_64 to the new irq-chip design.
As a bonus side-effect of the irq-chip approach, chained interrupt controllers
(master/slave PIC constructs, etc.) are now supported by design as well.
The end result of this patchset intends to be simpler architecture-level code
and more consolidation between architectures.
We reused many bits of code and many concepts from Russell King's ARM IRQ
layer, the merging of which was one of the motivations for this patchset.
This patch:
rename desc->handler to desc->chip.
Originally i did not want to do this, because it's a big patch. But having
both "desc->handler", "desc->handle_irq" and "action->handler" caused a
large degree of confusion and made the code appear alot less clean than it
truly is.
I have also attempted a dual approach as well by introducing a
desc->chip alias - but that just wasnt robust enough and broke
frequently.
So lets get over with this quickly. The conversion was done automatically
via scripts and converts all the code in the kernel.
This renaming patch is the first one amongst the patches, so that the
remaining patches can stay flexible and can be merged and split up
without having some big monolithic patch act as a merge barrier.
[akpm@osdl.org: build fix]
[akpm@osdl.org: another build fix]
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
This isn't really a dangerous thing any more; most systems lack
ISA interrupt controllers.
Signed-off-by: Olof Johansson <olof@lixom.net>
Signed-off-by: Paul Mackerras <paulus@samba.org>
In some crash scenarios, the kexec CPU is not responding to an IPI sent by
secondary CPU after init thread is forked, causing the system to drop into
xmon during kdump boot. This problem can be reproduced each time when the
debugger is enabled and soft-reset is used to invoke kdump boot. The first
CPU sends an IPI - setting the IPI priority for all secondary cpus
(xics_cause_ipi()). But some CPUs will enter into the xmon via soft-reset,
i.e, not executing xics_ipi_action(). Hence, IPI is not cleared. When
exited from the debugger, one of these CPUs could become the primary kexec
CPU. Since the IPI is not cleared, causing this issue in kdump boot. This
patch clears and EOI IPI for kexec CPU as well before the kdump boot
started.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Also cleans up some nearby whitespace problems.
Signed-off-by: Segher Boessenkool <segher@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
for_each_cpu() actually iterates across all possible CPUs. We've had mistakes
in the past where people were using for_each_cpu() where they should have been
iterating across only online or present CPUs. This is inefficient and
possibly buggy.
We're renaming for_each_cpu() to for_each_possible_cpu() to avoid this in the
future.
This patch replaces for_each_cpu with for_each_possible_cpu.
Signed-off-by: KAMEZAWA Hiroyuki <kamezawa.hiroyu@jp.fujitsu.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
We currently have a hack to flip the boot cpu and its secondary thread
to logical cpuid 0 and 1. This means the logical - physical mapping will
differ depending on which cpu is boot cpu. This is most apparent on
kexec, where we might kexec on any cpu and therefore change the mapping
from boot to boot.
The patch below does a first pass early on to work out the logical cpuid
of the boot thread. We then fix up some paca structures to match.
Ive also removed the boot_cpuid_phys variable for ppc64, to be
consistent we use get_hard_smp_processor_id(boot_cpuid) everywhere.
Signed-off-by: Anton Blanchard <anton@samba.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It has been decreed that platform numbers are evil, so as a step in that
direction, replace platform_is_lpar() with a FW_FEATURE_LPAR bit.
Currently FW_FEATURE_LPAR really means i/pSeries LPAR, in the future we might
have to clean that up if we need to be more specific about what LPAR actually
means. But that's another patch ...
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
These symbols are only used in the file that they are defined in,
so they should not be in the global namespace.
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Implementing the machine_crash_shutdown which will be called by
crash_kexec (called in case of a panic, sysrq etc.). Disable the
interrupts, shootdown cpus using debugger IPI and collect regs
for all CPUs.
elfcorehdr= specifies the location of elf core header stored by
the crashed kernel. This command line option will be passed by
the kexec-tools to capture kernel.
savemaxmem= specifies the actual memory size that the first kernel
has and this value will be used for dumping in the capture kernel.
This command line option will be passed by the kexec-tools to
capture kernel.
Signed-off-by: Haren Myneni <haren@us.ibm.com>
Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>
It turns out that commit f9bd170a87
broke the cascade from XICS to i8259 on pSeries machines; specifically
we ended up not ever doing the EOI on the XICS for the cascade. The
result was that interrupts from the serial ports (and presumably any
other devices using ISA interrupts) didn't get through. This fixes
it and also simplifies the code, by doing the EOI on the XICS in the
xics_get_irq routine after reading and acking the interrupt on the
i8259.
Signed-off-by: Paul Mackerras <paulus@samba.org>
This patch merges platform codes. systemcfg->platform is no longer used,
systemcfg use in general is deprecated as much as possible (and renamed
_systemcfg before it gets completely moved elsewhere in a future patch),
_machine is now used on ppc64 along as ppc32. Platform codes aren't gone
yet but we are getting a step closer. A bunch of asm code in head[_64].S
is also turned into C code.
Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>
Use __do_IRQ instead. The only difference is that every controller
is now assumed to have an end() routine (only xics_8259 did not).
Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
This patch moves the XICS interrupt controller code into the
platforms/pseries directory, since it only appears on pSeries
machines. If it ever appears on some other machine we can move it to
sysdev, although xics.c itself will need a bunch of changes in that
case to remove pSeries specific assumptions.
Signed-off-by: David Gibson <dwg@au1.ibm.com>
Signed-off-by: Paul Mackerras <paulus@samba.org>
